Pigment and long-distance exchange
Obsidian carried 90 kilometres and processed red and black pigments imply networks and symbols.
- When
- —
- Duration
- 25 thousand years
- Known to
- ± 15 thousand years
- Era
- Middle Pleistocene, Quaternary
The same Olorgesailie deposits contain obsidian from sources up to 90 kilometres away — far beyond a normal foraging range, implying either long expeditions or exchange between groups — together with lumps of red ochre and black manganese showing signs of having been worked to extract colouring material. Neither has a practical function that explains the effort. Together they are among the earliest indications of social networks extending beyond the immediate band, and of colour used for something.